Summary of the 2018 Mammalian DNA Repair GRC and GRS The focus of this 5 day GRC + 1.5 day GRS conference is on the mechanisms that maintain genome stability. Our genome is constantly challenged by environmental and endogenous sources of DNA damage and replication stress. Environmental mutagens include radiation, aldehydes, and dioxins. Endogenous sources of damage include reactive oxygen species and the normal instability of the DNA backbone. A multitude of DNA repair and DNA damage response mechanisms successfully operate to maintain genome stability. However, failures do happen resulting in diseases ranging from rare developmental and premature aging syndromes to common cancers. This Mammalian DNA Repair Gordon Research Conference (GRC) and associated Gordon Research Seminar (GRS) will bring together diverse researchers studying the mechanisms that maintain genome stability and the consequences for human health when these mechanisms fail. In addition, the conference will explore opportunities that DNA repair and signaling networks provide for therapeutic intervention in cancer, and discuss how we can harness these DNA metabolic enzymes for genome editing. The objectives are: 1) To expose researchers at all levels (faculty, researchers from industry, postdoctoral fellows, and graduate students) to new frontiers of this rapidly progressing research field. 2) To provide opportunities for young scientists to network and practice presenting their research. 3) To generate an atmosphere of inclusion and rigor that encourages the exchange of scientific ideas that may foster collaborations or spur new innovation.4) To provide formal and informal career development opportunities. We will achieve these objectives by assembling diverse speakers and poster presenters. 40% of the invited speakers in the GRC are women and we expect approximately 45% of the GRS speakers be female trainees. This GRC/GRS is notable compared to meetings on similar topics for the amount of unpublished research that is presented, as well as the extensive informal discussion time during sessions, meals, and free time.